Poor outcome of patients with pulmonary adenocarcinoma showing decreased E-cadherin combined with increased S100A4 expression.

A loss or reduced expression of E-cadherin, the main cell-to-cell adhesion molecule, correlates with distant metastasis in various cancers. Recent studies have reported a close correlation between the expression of E-cadherin and that of S100A4, calcium-binding protein. In this study, we investigated the expression of E-cadherin and S100A4 status in relation to the clinicopathological parameters of pulmonary adenocarcinoma. We finely and quantitatively examined the expression of E-cadherin and S100A4 using real-time polymerase chain reaction (PCR) in a total of 92 pulmonary adenocarcinomas obtained by surgical resection. All of the pulmonary adenocarcinomas showed significant expression of E-cadherin and S100A4. Real-time PCR showed lower E-cadherin expression in 21 adenocarcinomas, while 71 adenocarcinomas expressed a higher expression of E-cadherin. Of 21 adenocarcinomas with lower-expressing E-cadherin, 12 showed a higher expression of S100A4. These 12 cases significantly showed a poorer prognosis than others (p=0.047, Kaplan-Meier, log-rank test) and significantly showed more frequent venous involvement than others (p=0.042, chi2 test). These results suggested that reduced E-cadherin expression combined with higher S100A4 expression is related to a poor prognosis through hematogenous metastasis in pulmonary adenocarcinoma.